Light emitting diode package structure and fabrication method

Abstract

A light emitting diode package structure allows for an improved light-emitting efficiency by including a first reflecting material layer with through holes; a flip chip on the first reflecting material layer, with the electrodes inlaid in the through holes of the first reflecting material layer; a first transparent material layer surrounding the side surface of the flip chip except the electrodes; and a second reflecting material layer surrounding the first transparent material layer. An interface between the first transparent material layer and the reflecting material layer is an inclined plane, an arc plane, or an irregular shape, to thereby facilitate upward light reflection of the flip chip. A wavelength conversion material layer is over the first reflecting material layer, the flip chip, and the second reflecting material layer.

The invention claimed is: 
     
       1. A light emitting diode package structure, comprising:
 a first reflecting material layer comprising a reflective glue with through holes; 
 a flip chip over the first reflecting material layer, with electrodes inlaid in the through holes of the first reflecting material layer; 
 a first transparent material layer comprising a transparent glue surrounding a side surface of the flip chip other than the electrodes; 
 a second reflecting material layer comprising a reflective glue surrounding the first transparent material layer, wherein an interface between the first transparent material layer and the second reflecting material layer is an inclined plane, an arc plane, or an irregular shape, to thereby facilitate upward light reflection of the flip chip; and 
 a wavelength conversion material layer comprising a fluorescent material. 
 
     
     
       2. The light emitting diode package structure of  claim 1 , wherein: an upper surface of the second reflecting material layer is flush with upper surfaces of the first transparent material layer and the flip chip, and makes the upper surfaces into a co-plane. 
     
     
       3. The light emitting diode package structure of  claim 2 , wherein: a selective optical film is arranged on the co-plane such that the selective optical film is between the co-plane and the wavelength conversion material layer. 
     
     
       4. The light emitting diode package structure of  claim 3 , wherein: the selective optical film is configured to transmit blue light and reflect green light, yellow light, and red light. 
     
     
       5. The light emitting diode package structure of  claim 1 , wherein: an inner edge of a bottom of the second reflecting material layer is in contact with a side surface of the flip chip. 
     
     
       6. The light emitting diode package structure of  claim 1 , wherein: an inner edge of a bottom of the second reflecting material layer has a gap from a side surface of the flip chip. 
     
     
       7. The light emitting diode package structure of  claim 1 , wherein: the first transparent material layer does not contain a wavelength conversion material. 
     
     
       8. The light emitting diode package structure of  claim 1 , wherein: the first transparent material layer contains a wavelength conversion material. 
     
     
       9. The light emitting diode package structure of  claim 1 , wherein: an interface between the first transparent material layer and the second reflecting material layer is an inclined plane, an arc plane, or an irregular shape. 
     
     
       10. The light emitting diode package structure of  claim 1 , wherein: an optical reflecting layer is inserted at an interface between the first transparent material layer and the second reflecting material layer. 
     
     
       11. The light emitting diode package structure of  claim 1 , wherein: the wavelength conversion material layer has a thickness of 5 μm-200 μm and a planar upper surface. 
     
     
       12. The light emitting diode package structure of  claim 1 , wherein: an upper surface of the wavelength conversion material layer is roughened. 
     
     
       13. The light emitting diode package structure of  claim 1 , wherein: an upper surface of the wavelength conversion material layer has an arc structure. 
     
     
       14. The light emitting diode package structure of  claim 1 , wherein: the wavelength conversion material layer has an optical lens. 
     
     
       15. The light emitting diode package structure of  claim 1 , wherein: the flip chip electrodes contain Cu or Au and have a thickness of 10 μm-100 μm. 
     
     
       16. A light emitting diode package structure, comprising:
 a first reflecting material layer comprising a reflective glue with through holes; 
 an inverted-trapezoidal flip chip on the first reflecting material layer, with electrodes inlaid in the through holes of the first reflecting material layer; 
 a second reflecting material layer comprising a reflective glue surrounding the inverted-trapezoidal flip chip, wherein an interface between the second reflecting material layer and the flip chip forms an optical cup for upward light reflection of the flip chip; and 
 a wavelength conversion material layer over the first reflecting material layer, the inverted-trapezoidal flip chip, and the second reflecting material layer. 
 
     
     
       17. The light emitting diode package structure of  claim 16 , wherein the light emitting diode package structure is manufactured by:
 providing a fluorescent film; 
 bonding a plurality of flip chips to the fluorescent film where the flip chip electrodes are distal from the fluorescent film; 
 forming a transparent material layer comprising transparent glue on the fluorescent film surrounding a side surface of the flip chip except the electrodes, wherein a side surface of the transparent material layer between adjacent flip chips is in U shape or V shape; 
 filling the first reflecting material layer on the flip chip and the transparent material layer; 
 grinding or blasting the first reflecting material layer till the flip chip electrodes are exposed such that the upper surface of the first reflecting material layer is not higher than the upper surface of the flip chip electrodes; and 
 forming a plurality of units by cutting along central lines of adjacent flip chips to obtain a light emitting diode package structure.